Small utility vehicles exist for various uses. For example, riding grass mowers having what is called zero turn radius have existed for some time, but these mowers are not designed for carrying and dumping loads of material like mulch, rock, dirt, hay bales, tools and other similar materials and articles.
Other small utility vehicles, some powered, are know for specific purposes. For example single wheeled wheelbarrows are known, but still require manual lifting for movement and dumping. U.S. Pat. No. 3,891,043 discloses a powered wheelbarrow having a single wheel up front being powered by an internal combustion engine drive and two handles for steering and dumping. An attached two wheeled seat and foot rest is connected to the rear of the wheelbarrow and has 2 un-driven wheels for the operator to ride on. The wheelbarrow is dumped with manual labor of the operator, thus undesirably limiting the hauling capacity to that which the operator can manually using the handles.
U.S. Pat. No. 4,645,264 discloses a powered front dumping vehicle or buggy that can be operated by the operator walking behind, standing on a rear platform or sitting on a seat mounted on the rear platform. This powered dumpster has spaced apart dual wheels at the front with a single swivel wheel at the rear. It is powered with an internal combustion engine driving a hydraulic pump, and using a hoisting cylinder and control valve the hopper is dumped. The drive comprises control valves and a hydraulic motor on each wheel driving the front dual wheels. The powered dumpster is steered with a handle or a steering wheel that moves the swivel wheel in the rear.
U.S. Pat. No. 5,284,218 discloses a motorized wheelbarrow having a front mounted internal combustion engine driving two spaced apart front wheels via belts and a manual operated belt tightener. The rear of the wheelbarrow is supported by two spaced apart swivel castor wheels in the rear. A handle like a lawn mower handle is mounted at the rear with the belt tightener or gear changing lever and a throttle. The wheelbarrow is steered by an operator using the handle and rear castor wheels, and the operator must manually dump the loaded wheelbarrow.
U.S. Pat. No. 6,155,648 discloses a motorized dumpster supported on spaced apart pairs of dual wheels at the front of the frame and a pair of closely spaced steerable wheels near the rear center of the frame. The motorized dumpster can be operated by walking behind or by folding down a platform at the rear and riding standing up. The motorized dumpster has a handlebar control at the rear of the vehicle. The handlebar has twist grips and one of the twist grips causes the motorized dumpster to move forward when twisted in one direction and backward in when twisted from neutral in the opposite direction. While individual hydraulic motors drive the front two wheel sets in forward, neutral and reverse, both wheel sets are driven at the same speed—steering is accomplished by turning the rear wheels with the handle bar. The motor also generates electricity that is stored in an AC charge coil and run through an AC/DC converter to two solenoids that activate and deactivate a hydraulic cylinder for dumping the bucket.
U.S. Pat. Nos. 6,293,627 and 6,578,924 disclose a front dumping motorized dumpster having a dump container and two spaced apart driven front wheels and at least one optionally driven, pivoting and centrally located rear wheel steered using a handle bar. The dump container is pivotally mounted on the front of the frame of the vehicle.
U.S. Pat. No. 6,997,667 discloses a typical Bobcat® equipped to accept numerous implements on the front end. It is steered by skidding, i.e. locking both wheels on one side while allowing the two wheels on the opposite side to drive, by steering all four wheels or by driving one wheel in an opposite direction as the opposing wheel. The drive system is not disclosed in detail. None of the wheels are swivel castor wheels.
Published Patent Application 20050196261 discloses a powered utility vehicle small enough to operate in confined spaces and that minimizes damage to landscape while providing such tasks as hauling and dumping. The vehicle comprises a frame, a motor, a drive train, a bed or box for supporting or containing a load, and a box dumping mechanism. It is stated that the track type drive system can be replaced with wheels and that known drive trains and drive systems can be used, but none are described in detail.